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Black Friday Calculator

Created by Arturo Barrantes and Hanna Pamuła, PhD
Reviewed by Bogna Szyk and Jack Bowater
Last updated: May 26, 2024

As THE day is coming, we present to you the Black Friday calculator - a super useful tool that can guide you through Black Friday deals and sales. As we've based this tool on "the queen of all sciences", we'll help you shop sensibly, not hot-headedly. In this calculator we've combined nine different types of deals: from the popular % off, through 2 for 1 or 3 for 2 offers, to common double and triple discounts, to make sure you're covered for every possible decision.

meme brace yourself

You need to remember that Black Friday is a feast day not only for shoppers, but also for dealers. The offers are usually really convincing, as retailers pull out all the stops - with marketing tricks designed to let your guard down. Do you know that - according to some research - 87% of popular items may be found at a cheaper price another time of the year? Thus, the most important thing is not to get caught in overwhelming shopping frenzy: use your common sense, research extensively, and - of course - arm yourself with our Black Friday calculator to answer: is Black Friday worth it?

We have a tool that will help you understand sale percentages. Just take a look at percent off calculator and be at ease while shopping.

Black Friday deals options

Nobody wants to do the math when a Black Friday super-mega-limited offer appears. You're in a hurry and are stressed that it will soon disappear. We understand completely. That's why you need to prepare in advance - check out the prices beforehand, search for the best deals in many different places and compare the offers. To make this task easier for you, we've built this Black Friday calculator to deal with nine popular kinds of deals so that you can use it whatever the saving.

Look at the picture and find the explanation down below.

most common black friday deals
  • % off (also called simply discount)

    Calculate the savings and final price by simple operations with percentages.

    Deal example: -35% off shoes, so 👠*65%

  • % off on second product

    Also, in the form "Buy one, get second X% off".

    Deal example: Buy a T-shirt, get 40% off the second,

    so 👕+👕*60%

  • % off on third product

    Similar to the previous option, but two products come at their standard price whereas only the third (the cheapest one) has a reduction.

    Deal example: Buy two bottles of wine, get 70% off the third bottle,

    so 🍷🍷+🍷*30%

  • 2 for 1

    This kind of deal is also 50% off two products if both items cost the same. If the prices differ, the cheaper item is discounted.

    Deal example: Buy one book, get a second for free,

    so 📘+📘*0%

  • 3 for 2

    Another type of BOGOF (buy one, get one free) offer: analogical to the 2 for 1 deal, but not so rewarding, as the maximum discount is 33.3%.

    Deal example: Buy two pizzas, get one free,

    so 🍕🍕+🍕*0%

  • 4 for 3

    Similar to the previous two deals, but usually the least profitable. The maximum discount you can get is only 25%, and that's the case when all the items are the same price.

    Deal example: Buy four tires for the price of three,

    so ⚫⚫⚫+⚫*0%

  • Double discount

    Sometimes you can find offers such as "50% + 30%". It doesn't mean that somebody doesn't know how to add 50 to 30: it says that the original discount was 50% off, then 30% was taken from the new price. So in total, for this example, the effective discount is 65%, not 80%.

    Deal example: Double discount on computer: 20% + 25%, effective discount is 40%, so 🖥️*60%

    The double discount calculator might help bring a bit more clarity to the concept.

  • Triple discount

    Similar to the previous deal, but the discounting happened three times.

    Deal example: Headphones triple discount: 10% + 10% + 20%, effective discount is 35.2%,

    so 🎧*64.8%

    Go, and check out the triple discount calculator and get a grasp on taking advantage of triple discount deals.

  • Discount on multiple units

    Also, you can find the deals such as buy N of the same item for $X.

    Deal example: buying a 5 pack of chocolate candy bars for $11, while the price per bar is $2.39 will save you $0.95.

    so 🍫🍫🍫🍫🍫 for 11$ instead of 5🍫*2.39$ = 11.95$

As an output for each discount option, you'll get information about the final price after the deal has been applied, and how much you have saved in comparison to the "standard" offer. Some deals have additional fields, such as e.g. savings as a percentage, average cost of one item or effective discount in case of double and triple discounts. We also try to assess whether it's a real Black Friday deal, or a rip-off in disguise.

What is Black Friday?

Black Friday is the unofficial start of the Christmas shopping season. Since 2005, it's been the US's busiest shopping day. Many retailers offer extra sales and special offers, while people storm the stores and websites. Every year many people are seriously injured or even die due to shootings or getting trampled to death. Before Black Friday 2022, the death toll was 17 dead and 125 injured. Please remember it's just shopping — calm down, and don't help to increase those numbers anymore.

meme from South Park, people storming the shop on Black Friday

When is Black Friday?

In 2022, Black Friday is on 25th November. As usual, it's the first Friday after Thanksgiving. Yes, you know, that day when you are thankful for everything in your life.

meme exploding head

We know it may be challenging when you're bombarded by ads and exclusive sales, but stay strong and try to maintain moderation while shopping. Simply ask yourself ten times if you really need this or that, and go for things you wanted to buy anyways, not because they are discounted on Black Friday.

Hey, just in case you need it, we have a discount calculator. It is sure to come in handy on your shopping spree.

Why is it called Black Friday?

The adjective black has usually had negative connotations throughout history:

  • Black Monday (October 19, 1987), a sudden and severe stock market crash
  • Black Tuesday (October 29, 1929), often called the beginning of the Great Depression
  • Black Wednesday (September 16, 1992), the pound sterling lost 15 percent of its value after withdrawing from the European Exchange Rate Mechanism
  • Black Thursday (October 24, 1929), beginning of the Wall Street Crash
  • ??? Black Friday ??? "Hey, let's organize a massive shopping spree!"

If you check the Wikipedia pages for Black Saturday and Black Sunday, you'll mostly find crises, massacres, riots, battles, deaths, and fires. Also, when you're check for events specific to Friday, it's no different. So why the heck did somebody coin the phrase 'Black Friday' to mean excessive sales and shopping - a somewhat positive connotation, huh?

To understand why it's called Black Friday, we need to go back several decades. The term was first officially used in a journal from November 1951, but with a slightly different context. It was introduced to describe the practice of taking sick leave the day after Thanksgiving🦃, to extend the long weekend to four days. Also, around the same period, police departments started to use "Black Friday" as a term to describe the extreme chaos, traffic, accidents and violence on the street due to the start of the Christmas shopping season.

The term spread and gained popularity over the years. In 1980 another explanation to why that day is called Black Friday appeared, more positive this time. The backstory for the name was the color of the ink used for listing financial records - at that time, it was a common practice to use red ink for financial losses and black ink for profits. The Friday after Thanksgiving was the day when consumers started their Christmas spending and the retailers finally could change the color from red to black.

Is Black Friday worth it? Things to check before shopping

There are plenty of different marketing tricks to persuade you to buy more than you need and want. So, before clicking the "Buy now" button, check:

  • If the original price hasn't been artificially boosted 📈

Often retailers cross out the old, "previous" price to show you that they've prepared a great deal for you. Its the opportunity of a lifetime. But don't get duped! Again, use price comparison sites, do the research, and make sure that the retailer didn't display the MSRP price (manufacturer's suggested retail price, which may be much higher than usual price) all of a sudden, or check whether the price hasn't been artificially raised two weeks before Black Friday.

  • Delivery costs (and minimum order values) 🚚

Sometimes the product may look like a real bargain, when really some of the cost has been passed onto the delivery cost. So you've added that discounted item of your dreams to your cart, you're proceeding through the order, you've almost there, that sweet taste of victory, so sweet... and when you reach checkout, you notice (or don't) that the deal is nothing special, as the shipping cost is irrationally high. That is why, we added a shipping cost feature in the amazing Black Friday Calculator. Whenever you see those trick that propose having minimum order value, so you have to add products that you don't really want just to get to the price, beware of using the shipping cost feature and verify if the deal really benefits you. Purchase more for delivery offers is a win-win situation for the shop as you're purchasing much more than you've planned. Don't let them take you in, just quit and start searching from the beginning.

  • Sales taxes any other hidden costs 💸

In the US, tax isn't included in the shelf price, so don't forget about that. And remember that you can find fine print almost everywhere, and Black Friday deals are no exception.

How to not get caught by marketing tricks

To take a lesson from Sun Tzu, "know thy enemy" - here are some sales tricks:

  1. Limited offers, time-limited deals... don't get trapped by FOMO, Fear of Missing Out ⏲️

We've all been there. If you check any booking site, be it for accommodation🛏️ or flights✈️, you'll be bombarded by changing prices and offers that won't stick around for long. Enter any shopping site, and you'll find offers almost shouting "now or never!", showing a very limited stock in red. But, eventually, you waited and it turned out that the stock lasts for the rest of the week! Clearly, the aim was to make you impulse buy.

Of course, limited deals like that exist (doorbusters deals), but they are mostly intended to create hype and attract you to the shop. Usually, there's not a very high chance that you'll buy that tremendously discounted item, but, hey, as you're around anyway, maybe you'd take a look round and buy something else? This is a really popular shopping strategy.

  1. Buy X, get one for free! 🆓

Everybody likes to get something for free, right? It sounds sooo good! But don't forget that you're still paying. Often the basic price is inflated, so really you're only getting a small discount - or even none at all. Not to mention "offers" which make you pay more than standard price.

  1. Inflated sales, false price reductions 🎈

Retailers will do anything to draw your attention and make deals look better than they really are. In many such cases, you can use our Black Friday calculator and check whether that 4 for 3 or % off the second product is worth considering. Also, comparing the price between stores is always a good idea.

meme from South Park, Black Friday deal

We've described a few popular sales hacks. Still, of course, there are many more marketing tricks: decoy pricing, offering "improved" products, pricing psychology (199$ vs. 200$), tripwire offers or product layout and visibility in a shop to name a few. If you want to know more about those techniques, check e.g. this outbound article or this medium post.

The take-home message from all of this is don't get lured by all those "great deals" and marketing tricks - be a conscious customer, remain clearheaded and reasonable at all times:

  1. Be aware of marketing methods
  2. Only buy the things you really need
  3. Stick to your preprepared list and budget

By following those three simple steps, we're sure that your Black Friday hunting will be rewarding and fruitful!

Arturo Barrantes and Hanna Pamuła, PhD
Related calculators
Get yourself prepared for the incoming Black Friday discounts! Use this tool to check how much you actually save on the deals. 💰🤑💰
What type of deal?
% off
Original price
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Your deal
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Including shipping
You're saving
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